My dream is to see the world choose an official world auxiliary language (if not a constructed language like Esperanto, a pre-existing language like English would be fine if that gets enough democratic agreement) so that in addition to fostering transparency and understanding in the world, unparalleled development can occur to benefit all world-wide (minus a handful of dictators and demagogues who thrive on keeping us all apart), with all of us having more direct access to each other as resources, such as here on Stack Overflow, in open source projects, for online education, and so on.

If you can think of an idea which would have a more profound impact, while being essentially not unimaginable to achieve, I'd really like to hear it...